Grindeb



July 21, 1931. R, PRATER 1,815,326

' GRINDER Filed Aug. 21, 1929 Patented July 21, 1931 STATES RALPH PRATER, OF DAK PARK, ILLINOIS GRINDER Application filed August 21, 1929.

Q ment of the rate of feed.

lilith this object in view my invention consist's in certain features of novelty in the construction, combination, and arrangement of parts by which the said object and certain other objects hereinafter appearing are effected all as fully described with reference to the accompanying drawings and more particularly pointed out in the appended claims.

In the said drawings- Figure 1 is a side elevation of a grinder embodying my invention with parts broken u yay and shown in section;

Figure 2 is an end elevation of the same with a part shown in section;

Figure 3 is an enlarged partial section on the line 3 3 of Figure 2.

Like characters of reference indicate like parts in the several views.

Referring to the drawings, 1 designates a casing within which extends a revoluble .alla ft 2 carrying hammers 3 which during rotation of the shaft grind material fed into the casing, the material being discharged through a sizing screen 4 at the bottom of the casing wien sufficiently reduced. See Figf ure 1.

The ends of the casing wall are vertical and i' one of these is provided with a feed aperture Serial No. 387,518.

provided with the feed aperture 5, y means of a headed screw 7, is a plate 8 provided with a feed opening 9 overlying the feed aperture 5. See Figures 1, 2 and 3.

Secured on the exterior face of the plate 8 is a pair of vertically extending parallel slides 11 arranged at opposite sides ofthe feed opening 9. Slidably mounted in these slides, and consequently disposed on the outer face of the plate 8, is a second transversely disposed plate 12 which in its movement in the slides 11 is vertically movable across the feed opening 9 for purposes hereinafter set forth.

The plate 12 is adjustably positioned vertically by means of a manually operable vertical screw crank 13 screwthreaded through a block 14 secured on the upper end of the plate 8 and having at its lower end a bearing` engagement with the turned over upper end of the plate 12, as designated at 15. See particularly Figure 3.

An upwardly facing bucket formation 16 is secured on the inner face of the plate 8 and extends about the feed opening 9 of this plate and provides a transversely disposed upwardly extending inclined lip member 17 at the discharge end of the hopper 6 over which material must pass in feeding into the grinder.

The plate 12 provides a downwardly extending lip member adj acently spaced inwardly of the hopper from the lip member 17 under which material must pass inl feeding into the grinder.

The plate 12 or lip member and the lip member 17 cooperate to control the liow or feed of material into the grinder, adjustment of the plate 12 downwardly decreasing the flow and adjustment of this plate upwardly increasing the iow.

By reason of the offsetting or horizontal spacing of the lip members a relatively small uniform feed Vof material into the grinder is provided without decreasing-the cross section of any portion of the feed passage to such an extent that the material is liable to clog and interrupt or interfere with the uniformity of the feed. Consequently a uniform feed at relatively slow rate is attainable In order that an extremely line or slow rate of feed may be provided the lip member 17 is provided at its upper or feeding edge with a V-shaped indentation 1S, so that the lower edge of the plate member may be adjusted considerably below the normal upper edge of the lipmember 17 without entirely cutting o the feed.

By reason of the fact that the entire regulating device is carried on the detachable plate 8, it may be removed or installed as a unit, thus providing for convenient inter.- change with other feed regulating devices if desired.

I/Vhile I have described and shown the preferredembodiment of my invention I do not wish to be limited to the precise details as changes may readily be made without departing from the spiriti of my invention, but having thus described my invention, I claim as new and desire to secure by Iietters Patent the I following z 1. Ina grinder the combination with a feed hopper, of a transversely disposed upwardly extendinglip member at the discharge end of said hopper, and a transversely disposed downwardly extending lip member adjacently spaced inwardly of the hopper from said upwardly extending lip member and cooperating therewith to control the feed of material from said hopper, one of said' lip members having an indentation at the feeding edge thereof, and means whereby one of said lip members is vertically adjustable with respect'to the other lip member to adjust said'feed.

2. In a grinder the combination with aI feed hopper, of a transversely disposed upwardly extending'inclined lip member at the discharge end of said hopper, a transverselyv disposed downwardly ext-ending vertically movablelip member adjacently spaced inwardly of the hopper from said'upwardly extending lip member and cooperating therewith to control the feed of material from said' hopper, said upwardly extendinnr lip member having a Vshaped' indentation at theV ing overlying the feed aperture of saidwall port-ion; an upwardly facing bucket formation secured onthe inner fac-e of said plate and extending about the feed opening ihereof and providing a-transversely disposed upwardly extending inclined lip member at'the discharge end of said hopper and provided with a V.-sha.ped indentation at its upper 

